Hall L L, Borke R C
Department of Physiology, Uniformed Services, University of the Health Sciences, Bethesda, MD 20814-4799.
J Neurocytol. 1988 Dec;17(6):835-44. doi: 10.1007/BF01216710.
A detailed morphometric evaluation of the somata and organelles of regenerating hypoglossal motoneurons from the rat was conducted. The volume of the hypoglossal nucleus and various parameters used to appraise neuronal size were estimated from 50 microns sections. The subcellular composition of randomly selected neurons was quantified from 1 micron and ultrathin sections. The volume of neuronal nuclei, nucleoli, mitochondria and lysosomes as well as the surface area of intracellular membranes were determined. Seven to 30 days following axotomy the volume of the hypoglossal nucleus was significantly diminished, undoubtedly reflecting dendritic retraction (P less than 0.05). Concomitantly, all estimates of neuronal size indicated significant neuronal enlargement (P less than 0.05). Ultrastructural alterations were most prominent 7 days following nerve transection: nucleolar volume was significantly increased, rough endoplasmic reticulum surface area was reduced, and non-Golgi smooth membrane surface area increased (P less than 0.05). In general, other organelles resisted the influence of axotomy and all ultrastructural parameters returned to control levels 21 to 30 days following the nerve transection. Functional recovery was detected in all animals 21 and 30 days following axotomy. The measured responses of axotomized hypoglossal motoneurons are similar to those reported for retinal ganglion cells of the goldfish (Whitnall & Grafstein, 1982, 1983), suggesting common metabolic events among these distinct neuronal populations following axonal transection.
对大鼠舌下运动神经元再生的胞体和细胞器进行了详细的形态计量学评估。从50微米厚的切片中估计舌下神经核的体积以及用于评估神经元大小的各种参数。从1微米厚切片和超薄切片中对随机选择的神经元的亚细胞组成进行定量分析。测定神经元细胞核、核仁、线粒体和溶酶体的体积以及细胞内膜的表面积。轴突切断后7至30天，舌下神经核的体积显著减小，这无疑反映了树突的回缩（P<0.05）。与此同时，所有神经元大小的估计值均表明神经元显著增大（P<0.05）。超微结构改变在神经切断后7天最为明显：核仁体积显著增加，粗面内质网表面积减少，非高尔基体平滑膜表面积增加（P<0.05）。一般来说，其他细胞器抵抗了轴突切断的影响，并且在神经切断后21至30天所有超微结构参数均恢复到对照水平。在轴突切断后21天和30天在所有动物中均检测到功能恢复。切断轴突的舌下运动神经元的测量反应与金鱼视网膜神经节细胞的报道反应相似（惠特纳尔和格拉夫斯坦，1982年，1983年），这表明轴突切断后这些不同神经元群体中存在共同的代谢事件。
